On 8/17/2012 3:40 PM, clipka wrote:
> Are you sure the ARM does support full double-precision IEEE floating
> point arithmetics?

 From the Raspberry PI site (http://www.raspberrypi.org), the FAQ contains:

   What SoC are you using?

   The SoC is a Broadcom BCM2835. This contains an ARM1176JZFS, with 
floating point, running at 700Mhz, ...

Not sure what a "SOC" is, but a Google for 'ARM1176JZFS' leads to:

 
http://infocenter.arm.com/help/topic/com.arm.doc.ddi0301h/DDI0301H_arm1176jzfs_r0p7_trm.pdf

which is 'ARM1176JZF-S Revision r0p7 Technical Reference Manual'. In 
that manual it states (page 20.3, item 20.2.1):

   20.2.1 An IEEE 754 standard-compliant implementation
   The VFP11 hardware and support code together provide VFPv2 
floating-point instruction implementations that are compliant with the 
IEEE 754 standard. Unless an enabled floating-point exception occurs, it 
appears to the program that the floating-point instruction was executed 
by the hardware. If an exceptional condition occurs that requires 
software support during instruction execution, the instruction takes 
significantly more cycles than normal to produce the result. This is a 
common practice in the industry, and the incidence of such instructions 
is typically very low.

Since the RPi runs Debian Linux (the 'Wheezy' version? I'm not familiar 
enough with Linux to tell you what that means). Anyway, the package 
repositories are not built expressly for the RPi but for 'armhf' (again, 
I can't tell you what that means). What I would deduce from this is that 
from a programmer's viewpoint, IEEE floating point is supported, 
otherwise there would need to be special ports of math-related software 
for the RPi -- and there are not.

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